Author: Dr Chin-Yun Lin, Dermatology Registrar, Sydney, Australia, 2013.
What is a desmoplastic trichoepithelioma?
Desmoplastic trichoepithelioma is a harmless facial skin lesion. It is an uncommon form of trichoepithelioma, with a reported incidence of 1 in 5000 skin biopsies in a cohort of British adults. It has also been called ‘sclerosing epithelialhamartoma’.
Desmoplastic trichoepithelioma grows from cells lining the hair follicle. It is classified as a benign adnexal or hair follicle tumour.
Desmoplastic trichoepithelioma is most often identified in middle-aged females, although it may also occur at other ages and in males. A lesion may have been present for many years before being brought to medical attention.
What does desmoplastic trichoepithelioma look like?
Desmoplastic trichoepithelioma typically present as a firm skin-coloured to red, annular (ring-shaped) plaque with a central dimple. It is usually found on the upper cheek. Desmoplastic trichoepithelioma is stable or may slowly grow up to 1 cm in diameter. Multiple lesions are quite rare.
How is desmoplastic trichoepithelioma diagnosed?
Desmoplastic trichoepithelioma is diagnosed on full-thickness skin biopsy. Small incomplete biopsies may cause uncertainty, as sclerosing basal cell carcinoma and microcystic adnexal carcinoma may appear similar. Resampling or re-excision may be necessary for definitive diagnosis or complete eradication in uncertain cases.
What is the treatment of desmoplastic trichoepithelioma?
True desmoplastic trichoepithelioma is a benigntumour with no malignant potential, so there is no need to remove them. However, it is best to keep the lesion under observation in case the diagnosis is incorrect, as basal cell carcinoma may look very similar.